how to fix P0171 code in my Toyota RAV4 Fifth Generation (2019-present)

Solution

1. Preparation

• Gather required tools and parts.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the battery to prevent electrical shorts.

2. Inspect and Repair Air Intake System

• Sub-steps:
  • Remove the engine cover if applicable.
  • Visually inspect the air intake hose for cracks or loose connections.
  • Tighten any loose clamps and replace any damaged hoses.
  • Reconnect the air intake after inspection.

3. Clean or Replace MAF Sensor

• Sub-steps:
  • Locate the MAF sensor along the air intake path.
  • Disconnect the electrical connector and remove the MAF sensor.
  • Clean the sensor with MAF sensor cleaner or replace it if damaged.
  • Reinstall the MAF sensor and reconnect the electrical connector.

4. Check Fuel System

• Sub-steps:
  • Use a fuel pressure gauge to check the fuel pressure at the fuel rail.
  • Compare the reading with manufacturer specifications. If the pressure is low, inspect the fuel pump and fuel filter.
  • Test the fuel injectors for proper operation using a multimeter.

5. Inspect Vacuum Lines

• Sub-steps:
  • Trace and visually inspect all vacuum lines for cracks or disconnections.
  • Replace any damaged or leaking vacuum hoses.

6. Check Engine Coolant Temperature Sensor

• Sub-steps:
  • Locate the coolant temperature sensor and unplug the electrical connector.
  • Use a multimeter to check the resistance of the sensor and compare it to manufacturer specifications.
  • Replace the sensor if readings are out of spec.